Vacuum tube



Nov. 15, 1927. 1,649,489

H. J. ROUND VACUUM TUBE Filed July 9. 1921 Svweutoa H.J. ROUND z auomw X /MW Patented Nov. 15, 1927.

UNITED STATES HENRY JOSEPH ROUND, OF LONDON, ENGLAND, ASSIGNOR T RADIO CORPORATION OF ALIERICA, A CORPORATION OF DELAWARE.

VACUUM TUBE.

Application filed July 9, 1921, Serial No. 483,490, and in Great Britain May 29, 1914.

(GRANTED UNDER THE PROVISIONS OF THE ACT OF MARCH 3, 1921, 41 STAT. I, 1318.)

grid, and an anode, the screen being connected through an inductance to a source of current, and the anode being also connected through a second inductance shunted by a condenser to the source of current, while the two inductances are so arranged that they interact on each other.

According to this invention I omit the screen from the interiorof the tube and I reduce the cross-sectional area of the tube between the filament and the anode so as to form a constriction through which the dis charge passes, and I place outside the tube and around the constriction a metallic coat ing of wire or foil, this coating being connected as was the screen through an inductance to the source of current.

Further, I arrange at each side of the constriction the poles of an electromagnet by means of the field of which the current can be adjusted to the required value.

This arran ement is illustrated by the accompanying rawing in which Fig. 1 shows a circuit including in improved tube, and Fig. 2 shows a modi cation thereof. V is the tube having a filament F and anode H.

The tube is reduced in the middle and round the reduced portion is arranged a coating of wire or foil S connected to a high tension generator G through an inductance R shunted by a condenser K. M M are the poles of an electromagnet.

PATENT OFFICE.

The anode H is also connected in the or'dinary way to the generator through an inductance R shunted by a condenser K and the circuits containing the inductances R R 40 i are arranged so as to interact on one another.

Having described my invention, what I claim is:

1. A vacuous tube containing'ahot cathode and an anode and having a constricted portion therebetween, a metallic sheet round the constricted portion, and an electroma net adjacent thereto.

2. In a vacuum tube, in combination a container having a constricted portion, a 5 cathode and an anode respectively on opposlte sides of said constricted portion, said anode having greater area than the cross section of the constricted portion and having its surface substantially parallel thereto, an electrostatic control element located in proximity to said constricted portion.

3. In a vacuum tube, in combination, a container having a constricted portion, a cathode and an anode respectively on opposite sides of said constricted portion, and an electrostatic control element outside said container and surrounding said constricted portion.

4. In a vacuum tube, a container having a relatively constricted portion, a hot electrode and an anode in said container, located respectively on opposite sides of said constricted portion, and a control electrode comprising a thin sheet of metal surroundin said constricted portion.

HENRY JOSEPH ROUND. 

